BitTorrent Sync allows you to sync unlimited files between your own devices, or share a folder with friends and family to automatically sync anything. File transfers are encrypted. Your information is never stored on a server in the cloud and your data is protected by private keys. BitTorrent Sync is specifically designed to handle large files, so feel free to sync original, high quality, uncompressed files.
BitTorrent Sync synchronizes your files using a peer-to-peer (P2P) protocol. This protocol is very effective for transferring large files across multiple devices, and is very similar to the powerful protocol used by applications like µTorrent and BitTorrent. The data is transferred in pieces from each of the syncing devices, and BitTorrent Sync chooses the optimal algorithm to make sure you have a maximum download and upload speed during the process.
BitTorrent Sync was designed with privacy and security in mind. All the traffic between devices is encrypted with AES cypher and a 256-bit key created on the base of the secret—a random string (20 bytes or more) that is unique for every folder.